1. Field of the Invention
The present invention relates to a novel microorganism belonging to the genus Flavobacterium, a hydrocarbon emulsifier and solubilizer and a separation method for organic-solvent tolerant microorganisms. To explain in greater detail, the present invention relates to a novel microorganism belonging to the genus Flavobacterium having an ability to decompose hydrocarbons, tolerance to sulfurous acids, tolerance to salinity, tolerance to organic solvents, and tolerance to pressure and a hydrocarbon emulsifier and solubilizer produced by the microorganism.
2. Prior Art
Recently, marine pollution resulting from oil products such as kerosene, heavy oil, and the like, has become increasingly frequent, and has created many problems. As a method of solving this type of problem, the development of a microorganism which can efficiently and easily decompose all the hydrocarbons contained in oil pollution at sea has been desired; however, a microorganism having sufficient capacity has not yet been discovered. Examples of microorganisms which convert and decompose simple hydrocarbons contained in oil have included microorganisms belonging to the genus bacillus, the genus Acinetobacter, the genus Pseudomonas, the genus Moraxella, the genus Arcadia, and the genus Candida, which have been isolated from earth or sea water; however, these are not satisfactory in that they do not possess the tolerance to salinity, tolerance to organic solvents, and the like, which are necessary for the decomposition of oil pollution and the like at sea.
In order to decompose oil pollution and the like floating at sea, it is necessary that a microorganism be able to efficiently decompose oil products such as kerosene and heavy oil and the like, and that such a microorganism possess tolerance to toxicity resulting from hexane, benzene, toluene, xylene which are the organic solvents contained in these oil products, tolerance to salt which is present in large concentrations in sea water, and furthermore, tolerance to pressure. A microorganism possessing all of these qualities has not yet been discovered.
On the other hand, a substance which can efficiently and easily emulsify and solubilize all hydrocarbons contained in oil pollution floating at sea has been sought as a means to solve such problems; however, the substance possessing such properties in sufficient amounts has not yet been discovered. Many scientists have conducted research in the field of emulsifying and solubilizing substances which are produced by microorganisms, and it has been discovered that a number of types of microorganisms belonging to the genus Bacillus, the genus Acinetobacter, the genus Pseudomonas, the genus Moraxela, and the genus Candida and the like produce substances which possess the ability to emulsify and solubilize oil products. However, even if such substances produced by microorganisms are used, it is not possible to efficiently emulsify and solubilize oil; for example, the emulsifying and solubilizing substances produced by the genus Acinetobacter are unstable, losing their effect in a short time period and the like.
Conventionally, in order to separate a microorganism possessing such tolerance, and particularly, tolerance to organic solvents, a method was adopted in which a sample was added to a culture medium containing organic solvents and cultured, and microorganisms growing in this culture medium were isolated. However, this method was not merely time-consuming, but also had extremely low separation efficiency.